const Print = function(dom, options) {
    if (!(this instanceof Print)) return new Print(dom, options);

    this.options = this.extend({
            noPrint: ".no-print",
            onStart: function() {},
            onEnd: function() {},
        },
        options
    );

    if (typeof dom === "string") {
        this.dom = document.querySelector(dom);
    } else {
        this.dom = dom;
    }

    this.init();
};
Print.prototype = {
    init: function() {
        let content = this.getStyle() + this.getHtml();
        this.writeIframe(content);
    },
    extend: function(obj, obj2) {
        for (let k in obj2) {
            obj[k] = obj2[k];
        }
        return obj;
    },

    getStyle: function() {
        let str = "";
        let styles = document.querySelectorAll("style,link");
        for (let i = 0; i < styles.length; i++) {
            str += styles[i].outerHTML;
        }
        str +=
            "<style>" +
            (this.options.noPrint ? this.options.noPrint : ".no-print") +
            "{display:none;}</style>";

        return str;
    },

    getHtml: function() {
        var inputs = document.querySelectorAll("input");
        var textareas = document.querySelectorAll("textarea");
        var selects = document.querySelectorAll("select");
        let cells = document.querySelectorAll(".cell");

        for (var k = 0; k < inputs.length; k++) {
            if (inputs[k].type == "checkbox" || inputs[k].type == "radio") {
                if (inputs[k].checked == true) {
                    inputs[k].setAttribute("checked", "checked");
                } else {
                    inputs[k].removeAttribute("checked");
                }
            } else if (inputs[k].type == "text") {
                inputs[k].setAttribute("value", inputs[k].value);
            } else {
                inputs[k].setAttribute("value", inputs[k].value);
            }
        }

        for (var k2 = 0; k2 < textareas.length; k2++) {
            if (textareas[k2].type == "textarea") {
                textareas[k2].innerHTML = textareas[k2].value;
            }
        }

        for (var k3 = 0; k3 < selects.length; k3++) {
            if (selects[k3].type == "select-one") {
                var child = selects[k3].children;
                for (var i in child) {
                    if (child[i].tagName == "OPTION") {
                        if (child[i].selected == true) {
                            child[i].setAttribute("selected", "selected");
                        } else {
                            child[i].removeAttribute("selected");
                        }
                    }
                }
            }
        }

        const tableNode = document.querySelectorAll(
            ".el-table__header,.el-table__body"
        );
        //el-table 打印预览的时候，宽度占满
        for (let k6 = 0; k6 < tableNode.length; k6++) {
            const tableItem = tableNode[k6];
            tableItem.style.width = "100%";
        }

        return this.dom.outerHTML;
    },

    writeIframe: function(content) {
        let w;
        let doc;
        let iframe = document.createElement("iframe");
        let f = document.body.appendChild(iframe);
        iframe.id = "myIframe";
        iframe.style = "position:absolute;width:0;height:0;top:-10px;left:-10px;";
        w = f.contentWindow || f.contentDocument;
        doc = f.contentDocument || f.contentWindow.document;
        doc.open();
        doc.write(content);
        doc.close();
        this.toPrint(w, function() {
            document.body.removeChild(iframe);
        });
    },

    toPrint: function(w, cb) {
        let _this = this;
        w.onload = function() {
            try {
                setTimeout(function() {
                    w.focus();
                    typeof _this.options.onStart === "function" &&
                        _this.options.onStart();
                    if (!w.document.execCommand("print", false, null)) {
                        w.print();
                    }
                    typeof _this.options.onEnd === "function" && _this.options.onEnd();
                    w.close();
                    cb && cb();
                });
            } catch (err) {
                console.log("err", err);
            }
        };
    },
};
const MyPlugin = {};
MyPlugin.install = function(Vue, options) {
    // 4. 添加实例方法
    Vue.prototype.$print = Print;
};
export default MyPlugin;